A super fast and most gorgeous bike ride is the ascent to the village of Capriglia from Pietrasanta.
My recommended departure (The route is feasible even in reverse, but it is more challenging) is from Pietrasanta in Piazza Statuto. Go uphill Via Capriglia and continue along this path in a magnificent climb among the olive trees until you reach the village of Capriglia that you cross until you reach the Muretto from which you have the best panorama that sweeps over the Ligurian Sea from Elba to Corsica and to Liguria (all visible on clear days, in exceptional ones you can also see the Maritime Alps and the Monviso).
At this point begins the descent towards Capezzano Monte where then begins the steep descent to return to Pietrasanta. I recommend you go down slowly, with the brakes pulled, enjoying the views that open up, always new, at every turn: dangerous is letting yourself get carried away by the euphoria of the descent and the desire to relax without making the slightest effort. Pay attention to the slippery road due to the presence of olive trees along the way and also to uphill cyclists and cars, even if you shall not meet more than three or four in the process.
Culinary note: At Capriglia you will notice the SOMS Club (Mutual Aid Relief) that I recommend if you want to get out of the routine of the restaurants in Pietrasanta.
Daniele the chef prepares from time to time fresh and always new menus based on what is available. Try marinated cod, anchovies with caramelized onions and all desserts.
Effort: Short (<20Km) but oh so intense!